Radar painting revisited

[ProfCrash]

A couple months ago I posted about concerns regarding the weather radar depiction. I finally had some time to quantify the expectation vs simulator.

for context I've simulated the beam of the radar in desmos: https://www.desmos.com/calculator/usvsrea3fa
So here is the situation at hand, True altitude is 5000 feet (ISA STD SL). There is precipiatation and the radar is manipulated from +14° to -14° with GCS off and On. Cloud Tops are 18000feet and bases are 1500 feet. With the exception of a slight shader intensity change there is no difference in the presented image:

GCS OFF

+14°

-14°

GCS ON

+14°

-14°

Here is why this is significant:

1. At -14° Tilt and 5000 feet the radar should only paint distances between +2.61nm and +4.4nm
2. At that location and heading, the only visible returns have a maximum elevation of +2100ft for Santa Catalina. But GCS is doing something very strange
   
3. At +14° and 50nm the lower lobe is at 61,000feet and the upper lobe is almost 101,000 feet
   
   So there is nothing to paint at those ranges
4. With the clouds set as they are (assuming precip all the way to the top of the cloud) then a tilt of -0.5° would be the maximum tilt to paint something at 20,000 feet and 50 miles

@Black-Square do you have any insight into what is going on here?